Hospital Noises Affect Brain Activity, Heart Rate in Patients

Typical hospital noises that frequently disrupt the sleep of hospitalized patients influence both cortical brain activity and increase patient heart rate, potentially having a negative impact on the patient's healing and cardiovascular health, according to research published online June 11 in the Annals of Internal Medicine.

TUESDAY, June 12 (HealthDay News) -- Typical hospital noises that frequently disrupt the sleep of hospitalized patients influence both cortical brain activity and increase patient heart rate, potentially having a negative impact on the patient's healing and cardiovascular health, according to research published online June 11 in the Annals of Internal Medicine.

In an effort to determine the effects of typical hospital noises by sound level and type on sleep disruption, Orfeu M. Buxton, Ph.D., of Harvard Medical School in Boston, and colleagues conducted a three-day polysomnographic study in a sound-attenuated sleep laboratory; the study involved 12 healthy volunteers.

The researchers found that the level of arousal and sleep disruption varied according to the level and type of sound and the patient's sleep stage. Compared with voices and other sounds, electronic sounds were the most arousing. Sounds presented during non-REM stage-3 sleep were less likely to result in sleep disruption than when presented during non-REM stage-2 sleep. When presented during REM sleep, however, response to sounds varied less and resulted in a more sustained elevation of instantaneous heart rate.

"This study systematically quantifies the disruptive capacity of hospital-recorded sounds on sleep," the authors write. "We further demonstrate that the arousal effects of noise on sleep include heart rate elevations, even when disruptions are brief and frequent. Heart rate effects may be particularly relevant to critical care settings, in which monitor alarms are very frequent."